I would keep this animal in his cage until it clears up.
If it were my animal I would give it some Bene Bac Plus paste. ( I have used this with chin's that have had soft droppings ) Not for diarrhea. Just soft poo. Clean your cage daily and all ledges. That gives you an idea if it clears up.
I have had success in using the amount the size of a pencil eraser. Once daily for a couple days. By day three if the animal still has soft droppings, then you need to see the vet. IF FOR ANY REASON THE ANIMAL GETS DIARRHEA, HEAD TO THE VET AS SOON AS POSSBILE!! Or your animal doesn't act right and is laying down or won't eat or drink. I also suggest you buy a scale and keep a monthly record of weight. It's a good indicator of sickness if the weight drops and you see no signs of illness.
See link for cat Bene Bac plus paste. That's what I use. Petsmart carries it as well.
http://www.drsfostersmith.com/product/prod_display.cfm?pcatid=3563
I leave my pellets in the cage and offer a lot of hay. Make sure your using a good pellet. No snack like junk in it. Chins need fiber. Not empty calories in the feed with junk added. Change your water over to clean drinking water bought at the store. A gallon labeled "drinking water" purified by reverse osmosis/deionization and or distillation. Scrub that water bottle and tube clean as a whistle before pouring the bottled water into it.
One thing you don't mention is how long you have had your pet. If you just got the animal and its running around, it could be stress. If you have had your animal and its running around, its eating everything. Wires, plastic, base boards, cardboard, well you get the picture. When they are out of your sight, they eat anything and everything!!! Thus anything they may have ingested that you did not see would be an irritant to the gut and could cause the soft droppings.
As mentioned, keep your playtime in an enclosed environment like a bathroom with everything cleared away that they can put their teeth in. If you use a bathroom, close the toilet lid. They will get up there one way or another.
I use this play pen at the link below. It is big enough that I can sit in it. This one is from Dr's Foster and Smith. While they are a bit pricy, you can put a sheet under it and drop a duster in, toys, and even yourself. Folds nice and flat and you never have to worry what those little fur balls get into. See link:
http://www.drsfostersmith.com/product/prod_display.cfm?c=6067+10431+6265&pcatid=6265
If you like the play pen.....order that large one. It needs to be the large pen as chins jump.
Good luck